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Energy differences between frozen core and all electrons correlated.
MP2, MP3, MP4, B2PLYP, CCSD, and CCSD(T)

For H2NCHCHNH2 (diaminoethylene)

Energies in Hartree
Methods with standard basis sets
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ aug-cc-pVDZ aug-cc-pVTZ daug-cc-pVDZ daug-cc-pVTZ
Moller Plesset perturbation MP2=FULL -0.001310 -0.006936 -0.006936 -0.005045 -0.016401 -0.017468 -0.017931 -0.074909 -0.075787 -0.033411 -0.089586 -0.068736 -0.009992 -0.060572 -0.011423 -0.070729 -0.011705 -0.072899
MP3=FULL         -0.015925   -0.017467       -0.092697 -0.071516 -0.009346 -0.061931     -0.011040  
MP4=FULL   -0.006596     -0.015972       -0.078589   -0.093451   -0.009304 -0.062195 -0.010721 -0.073204 -0.011000  
B2PLYP=FULL -0.000395 -0.002067 -0.002067 -0.001501 -0.004840 -0.005146 -0.005282 -0.021356 -0.021619 -0.009697 -0.025685 -0.019621 -0.002962 -0.017554 -0.003385 -0.020421 -0.003467 -0.021032
Quadratic configuration interaction QCISD(T)=FULL         -0.015927           -0.093258   -0.009253 -0.062074 -0.010661   -0.010939  
Coupled Cluster CCSD=FULL         -0.015743         -0.033456 -0.092389 -0.071381 -0.009128 -0.061583 -0.010519   -0.010794  
CCSD(T)=FULL         -0.015933           -0.093249 -0.071817 -0.009255 -0.062081 -0.010663 -0.073080 -0.010941  
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ aug-cc-pVDZ aug-cc-pVTZ daug-cc-pVDZ daug-cc-pVTZ